3 Answers
3

As suggested by BlueRaja - To further my comment on StrixVaria's answer:

You should be able to create a deeper pool using source blocks that you place against a temporary vertical surface.

Basically, fill the bottom of your pool with sources by dropping buckets of water. Keep dropping water until the surface is flat, if you can see water flow into a square, then thats where the source needs to go. This will give an even 1 deep pool.
You're not finished yet.

B is solid blocks.

W is water sources.

B B
B B
BWWWWWWB
BBBBBBBB

Build a line of blocks directly over the water sources, this will give you a surface to drop a line of water sources against.

N is the line of new blocks (from the side).

B B
B N B
BWWWWWWB
BBBBBBBB

Start dropping another layer of water sources in the "trench", using the sides of the pool and the sides of the line of blocks to drop the sources against.

B B
BWWB B
BWWWWWWB
BBBBBBBB

Create a new line of blocks just outside of the existing one, then remove the existing line.

B B B B
BWWBN B -> BWW N B
BWWWWWWB BWWWWWWB
BBBBBBBB BBBBBBBB

Drop another line of sources against the inside of the new line of blocks.

B B
BWWWB B
BWWWWWWB
BBBBBBBB

Continue across the surface of the pool until you've filled in the second level. A third level can be placed in the same way.

BWWN B
BWWWWWWB
BWWWWWWB
BBBBBBBB

Note that it's possible to simply ignore the lower levels and just have an area of sources on the surface, like this:

BWWN B BWWWWWWB
B B > B B
B B B B
BBBBBBBB BBBBBBBB

This can still be used to provide a pool deep enough to fall into, and which can be removed more easily than a solid pool of sources.

Shouldn't water fall down if you put W against a vertical surface? I thought that was the way you could create waterfalls...
–
EmilianoNov 11 '10 at 15:06

6

@happy_emi: The water flows downward from the source, rather than the source falling down. The source stays were it was placed thus creates the waterfall. In the last example I gave, a surface of sources effectively creates a pool as the flowing water fills the basin beneath.
–
KurleyNov 11 '10 at 18:08

1

A more efficient variation on this would be to create rows of blocks with a 3-wide gap between. Then, walking along a row, drop a water source against the sides of each row (like so #W.W#W.W# - W=water, #=block, .=air) every other block. Each water block will flow outward, and when it encounters the flow from another water block 2 blocks away, a new "source" water block will be generated between them. This should propagate along the rows as well as between them, given a little time.
–
Doktor JMay 12 '11 at 20:47

1

@Doktor Source blocks can only be created when a solid block is underneath so there will still be flows on all but the bottom layer.
–
Ronan FormanAug 26 '11 at 23:09

Water physics in minecraft is nothing like what you would expect from true dynamic water physics.

Water has source blocks and other blocks. Source blocks can be picked up in a bucket and placed elsewhere, whereas other blocks simply run off existing source blocks and cannot be collected. Water runs up to 7 blocks away from a source block on flat ground, and can go further if there is a slope. You can read more about water physics at the minecraft wiki.

To answer your question on how to make water deeper, you have to manually collect source blocks and place them at the height you want the water. I have never quite been able to get a customized lake more than 1 level deep to work, but I know if you are patient enough you can place enough water blocks to manage it.

You can place a water source against any solid vertical surface, so if you place them in a trench, then make it 1 block wider each time it should be possible to make a multi height pool of sources. I did this another way, but it involved letting the blocks freeze in a winter biome.
–
KurleyNov 10 '10 at 14:35